1. Field of the Disclosure
The present disclosure is directed to scintillators, particularly ruggedized scintillator devices for industrial applications.
2. Description of the Related Art
Scintillation detectors have been employed in various industrial applications, such as the oil and gas industry for well logging. Typically, these detectors have scintillator crystals made of an activated sodium iodide material that is effective for detecting gamma rays. Generally, the scintillator crystals are enclosed in tubes or casings, which include a window permitting radiation induced scintillation light to pass out of the crystal package for measurement by a light-sensing device such as a photomultiplier tube. The photomultiplier tube converts the light photons emitted from the crystal into electrical pulses that are shaped and digitized by associated electronics that may be registered as counts and transmitted to analyzing equipment. In terms of well logging applications, the ability to detect gamma rays makes it possible to analyze rock strata as gamma rays are emitted from naturally occurring radioisotopes, typically of shales that surround hydrocarbon reservoirs. Today, a common practice is to make measurements while drilling (MWD). For MWD applications, the detector should be ruggedized, that is, it should have a high shock resistance and be capable of withstanding high temperatures, while maintaining performance specifications for a reasonable lifetime.
A problem associated with MWD applications is that the detector will report a higher than an actual count rate if the scintillation device detects false counts via vibration induced counts. Therefore, falsely high readings may occur due to the fact that the detector output will be composed of radiation-induced counts and vibration-induced counts. Moreover, the problem is exaggerated when detecting low-level radiation events while the detector is subject to a severe operational environment, such as drilling.
Accordingly, the industry continues to need improvements in scintillator devices, particularly ruggedized scintillator devices that can withstand the harsh environments of industrial applications, such as high shock and high temperature applications common in drilling. In addition, it is desirable to provide ruggedized scintillator devices that maintain detecting performance over an extended lifetime.